The present invention relates to spectral Doppler ultrasound. In particular, automatic optimization of spectral Doppler ultrasound imaging is provided.
Spectral Doppler ultrasound imaging provides a two-dimensional image of velocities (vertical scale) values modulated by energy as a function of time (horizontal scale) for studying fluid flow within a patient. By transmitting a plurality of pulses at a single gate location, a spectral Doppler response is generated in response to received echo signals.
Sonographers manually adjust the gate location, gate size, transmit frequency and other spectral Doppler imaging control parameters in order to acquire a desirable image. This process may be tedious and inexact, resulting in suboptimal spectral Doppler imaging. For example, the desired location of the spectral Doppler gate is typically at a position associated with the maximum flow velocity. A user may inexactly position the range gate at a different, adjacent position. As another example, an initial transmit frequency is selected by the user by adjusting the transmit frequency to different values until the image is subjectively correct, but not necessarily optimal.
Some processes have been proposed for automatic placement of the spectral Doppler gate. For example, a two-dimensional Doppler image of energy or velocity information is acquired. A position within the two-dimensional image associated with the maximum velocity or energy is selected for positioning of the spectral Doppler gate. Another proposed algorithm also samples at a plurality of predefined locations. In particular, the spectral power is calculated at multiple predefined locations in a one, two or three-dimensional grid. The location with the greatest spectral power is selected for the spectral Doppler gate position. However, sampling at predefined locations, such as for a two-dimensional image, may require extra processing and time.
Other spectral Doppler parameters may be automatically set, such as the size of the gate, ideal line angle and point of origin on the transducer.